K3OSO
Available1x3District 3
Competitive callsign — 2 applications filed with the FCC.
License HolderGrachev, Aleksey
License ClassAmateur Extra
Min. Class RequiredGeneral
LocationWestminster, CO
Grant DateMay 5, 2009
Expiration DateMay 5, 2019
Cancellation DateFeb 1, 2011
Available for ApplicationsFeb 2, 2013
K3OSO is a highly sought-after 1x3 format amateur radio callsign. The license is currently held by Grachev, Aleksey in Westminster, CO. This callsign has attracted significant interest in the amateur radio community, with 2 vanity applications filed with the FCC. The most recent was submitted by Lee, Annette Y on Sep 29, 2025. K3OSO has 7 recorded FCC license history events.
CW & Voice Analysis
Morse Code
-.- ...-- --- ... ---
CW Weight: 37 units(Moderate)
Voice Phonetics
Kilo Three Oscar Sierra Oscar
Readability: 7.5/10(High readability)
This callsign is available now
Requires General license or higher to apply for this callsign format (1x3).
License History
- License CanceledFeb 1, 2011
- Administrative Update AppliedNov 20, 2010
- License ModifiedNov 18, 2010
- License ModifiedJun 12, 2009
- Administrative Update AppliedMay 7, 2009
- License IssuedMay 5, 2009
- Vanity Callsign GrantedMay 5, 2009
Vanity Application Activity
Competing applications filed with the FCC for this callsign.